DW: Authorities are said to have used voice and facial recognition techniques to identify Mohammed Emwazi as Londoner 'Jihadi John'. How reliable are these methods?

Paul Beaver: Modern technology, using super-computers and voice-matching has progressed in leaps and bounds since 2000, driven by the need to identify AQ [al Qaeda] seniors. Facial recognition is now so advanced that computer matching of between 10 and 20 percent of a person's face/head can lead to identification. The Israel Defense Forces had such technology as early as 2007.

Emails from Emwazi indicate that he may have become radicalized after being detained by authorities in Britain at an airport, having been accused of having links to terrorist organizations. Is there any risk that counter-intelligence operations in the West might be playing a role in the radicalization of individuals?

This is such rubbish. This is an excuse. In 20 years of fighting PIRA [editor's note: official initialism for the Northern Irish group often called the IRA] and Real IRA operatives, not one to my recollection, ever said they had been radicalized as an Irish nationalist terrorist through the activities of the security services. Emwazi must have a weak personality to be radicalized in this way but the security services should take these theories into consideration. The problem in the UK (and the rest of Europe) is that there are individuals and groups ready to blame the slightest perceived provocation to give them an excuse to be radicalized.

A few cases of "homegrown jihadis" in Germany have sparked a debate about Islamic State propaganda and the people it is targeting, namely under-privileged, poorly integrated people. Yet Mohammed Emwazi has a middle-class background and a university degree in computer programming. Are well-educated, well-off people just as likely to become radicalized as the less advantaged?

Emwazi was privileged. Kuwaiti background meant family money, good school and tertiary education. There is a risk of any Muslim being seduced by radical Imams - Britain allowed in many from Somalia, Saudi and Egypt in the 1997-2010 period because the Muslim population had grown and there were no home-grown Imams to service their pastoral needs. These clerics were allowed in without proper background checks. The fact that middle-class terrorists exist - Germany had them in the 1970s too - rather dispels the idea that it is a reaction to poor housing, lack of job opportunities and the need for a job. Rather, it would seem to be the need for an identity.

There are said to be around 700 British militants fighting with Islamic State in Syria and Iraq. Leaving the sophistication of the group's propaganda strategies aside, what is prompting these people to sacrifice their lives for a cause so far away from home?

The current UK government informal estimate is 1,200 radicalized men and women with DAESH [an Arabic acronym for the Islamic State] and East African groups. Emwazi's own heritage seems to be from the Somalia extremist groupings which is very appealing to the Muslim youth which is seeking an identity in a modern world which is so different from the pre-medieval teachings of their Imams. Many do not think they will sacrifice their lives and if they do, they will be martyrs. It is a sad reflection on my generation in Europe that we did not understand the risks and did not find a proper 'prevent' strategy until it was almost too late.

A polarization of value systems seems to be taking place in Western societies, with Islamist extremism on the one side and far-right fundamentalists on the other. How far do you think this will go before it starts to change? What will it take to turn it around?

I am not at all optimistic. If we react forcefully, we will be playing into the arms of the Islamists; if not, we will have more terrorism. Irish terrorists were never keen to sacrifice their lives for the 'Cause' but DAESH, AQ, etc seem to be. What concerns the UK is that young girls are attracted to DAESH when it must be known just how subjugated the women are likely to be. More effort is needed in prevention and the Islamic establishment needs a reformation - Europe was like radical Islam in the 15th Century until the (mainly German) clerics reformed the thinking which had led to the Spanish Inquisition and cruel/unusual punishments.

Paul Beaver is a British terrorism and defense analyst and a parliamentary advisor on security affairs.

Interview conducted by Sarah Berning